LIBELLULA. 213 
and of cells in all the triangles and rather denser post-triangular fields, although the 
correlation is not precise nor very useful as a means of separating these two forms. 
5. Libellula nodisticta. 
Libellula nodisticta, Hagen, Syn. Neur. N. Amer. p. 151 (1861)’; Rep. U. 8. Geol. Surv. Terr. 
1872, p. 727 (1873)?; 1873, p. 583 (1874) °; Proc. Bost. Soc. Nat. Hist. xvii. p. 68 (1875) *; 
Ris, Mitt. schweiz. ent. Gesell. x. p. 438 (1902) ’. 
Leptetrum nodistictum, Kirby, Cat. Odon. p. 26 (1890) °. 
Females and young males have the frons superiorly pale olive with a transverse black stripe immediately in 
front of the vertex and eyes; in old males the entire upper surface is bluish-black. 
In the Mexican examples there is usually no black on the lateral labial lobes; in those from the United States 
a black band of variable width extends along the mesal (opposing) margin. 
While the basal blackish streak on the wings is usually clearer in the median space, the Jalisco female and one 
female from Reno have the streak completely separated into two streaks, occupying the subcostal and the 
submedian spaces respectively, on the hind wings ; on the front wings it is entirely confined to the sub- 
costal space (Jalisco), or is present in the subcostal space and the extreme base only of the submedian 
space (Reno) ; in neither female does the subcostal streak on the front wings extend beyond the level of 
the proximal side of the internal triangle, nor on the hind wings beyond the level of the proximal side 
of the discoidal triangle. 
Hab. Unirep States, Montana ‘4, Yellowstone 2°, Beaver Cafion in Utah (Hngelhardt 
and Doll, Brookl. Inst.: 1 3,1 2), Reno in Nevada (Hillman, coll. P. P. C.: 3 2), 
Los Angeles [ Davidson: 1 2], and Ontario [Snodgrass: 14 | (coll. P. P. C.) in Cali- 
fornia.—Mexico 13 (Schumann: 1 3), Las Bocas in Durango (Batty*, A. M. N. H.: 
1 2), Guadalajara (Schumann: 3 3, 3 2) [1 ¢], El Castillo [1 ¢ ] (McClendon, 
U.S. N. MW.) in Jalisco (Schumann: 1 2), Uruapam (Deam: 1 3), Mexico city 
(Schumann, H. H. Smith, Barrett, Deam, &c., &e.: 8 3, 11 2), Chapultepec 
(Barrett, coll. Adams : 2 3), Amecameca in Morelos (Ff. D. G.: 1 ¢ ).—CoLomBia °; 
VENEZUELA °. 
Taken in June (El Castillo), July (Beaver Cafion, Ontario, Guadalajara, Uruapam, 
Mexico city), and August (Reno, Las Bocas, Guadalajara). 
6. Libellula luctuosa. 
Libellula luctuosa, Burm. Handb. Ent. ii. p. 861 (1839)*; Hagen, Syn. Neur. N. Amer. p. 152 
(1861) ?; Calvert, Trans. Amer. Ent. Soc. xxv. p. 93 (1898)°; Ent. News, xvii. p. 80 (1906) *, 
Belonia luctuosa et odiosa, Kirby, Cat. Odon. p. 29 (1890) °. 
Libellula basalis, Say, Journ. Acad. Nat. Sci. Philad. viii. p. 23 (1839) °; Hagen, Proc. Bost. Soc. 
Nat. Hist. xviii. p. 70 (1875); Calvert, Trans. Amer. Ent. Soc. xx. p. 255 (1893) °; Kellicott, 
Canad. Ent. xxvi. p. 347 (1894)°; Odon. Ohio, p. 96 (1899)"°; Elrod, Ent. News, ix. p. 10 
(1898)"; Dury, Journ. Cincin. Soc. Nat. Hist. xix. p. 170 (1900) %; Williamson, 24th Rep. 
Geol. Indiana, p. 329 (1900) "; Ent. News, xiv. p. 229 (1903) “; Needham, Bull. 47, N.Y. St. 
* Notes on the localities at which Mr. J. H. Batty collected are given in Bull, Amer. Mus. Nat. Hist. 
(New York), xix. pp. 590 ef seq., xx. pp. 205 et seq., and ‘ Science,’ Oct. 20, 1905, p. 510. 
BIOL. CENTR.-AMER., Neuropt., April 1906. 9d f 
